AS3 Eval/Scripting Engines

AS3 Scripting Lib:

Compile AS3/JavaScript at runtime within the Flash Player
Execute compiled code in the scope of any object
Control which classes and functions are exposed to the script domain

https://code.google.com/p/as3scriptinglib/

D.eval:

The D.eval API brings the eval() functionality to ActionScript3 programming.

http://o-minds.com/deval/
http://www.riaone.com/products/deval

Runtime expression evaluation in ActionScript:
http://www.sephiroth.it/weblog/archives/2008/04/runtime_expression_evaluation_in_acti.php

ActionScript 3 Mathematics Expression Parser:
http://www.flashandmath.com/intermediate/mathparser

Lua for Flash:
http://code.google.com/p/lua-alchemy/ (Lua for Flash via Alchemy)
https://github.com/adobe-flash/crossbridge/tree/master/samples/Example_Lua
http://gonchar.me/blog/goncharposts/2121 (Lua for Flash via CrossBridge)
https://github.com/chadrem/easy_lua (Another Lua for Flash port using CrossBridge)
http://code.google.com/p/lufacode/ (Lua for Flash in pure AS3)

ActionScript 3 Eval Library:

As3Eval is a library that packages the Tamarin ESC compiler to work within a run-of-the-mill flash player.

http://eval.hurlant.com/

Governor:

Governor is a script engine written in AS3. It provides all functions and operators you know from AS3; operators, math functions, math constants. Additionally it provides multithreading functionality for parallel execution of code. !The flash player is design as a single thread application, so governor is providing green threads! 

http://code.google.com/p/governor/

BISE Scripting Engine:(Recommended)

The AS2-based engine could run a subset of ECMAScript, and it allowed users to write interpreted scripting for Flash games or applications. It also had some useful features, such as coroutines, a type of function that had the ability to suspend in the middle of its scripting.

http://kinsmangames.wordpress.com/bise-scripting-engine/ (AS3 Port)
http://kinsmangames.com/beinteractive-scripting-engine-bise-as3-port/
http://sourceforge.net/projects/biseas3/files/beinteractivescriptingengine_as3port_version104.zip/download
http://www.be-interactive.org/index.php?itemid=7 (AS2)

eval() for Actionscript 3:
http://www.brainblitz.org/anthony/130

AS3 Commons Bytecode:

AS3Commons-bytecode is an open-source library providing a ABC bytecode parsing and publishing and bytecode based reflection API for ActionScript 3.0. 

http://www.as3commons.org/as3-commons-bytecode/

XML to ActionScript(asXML):
http://actionsnippet.com/?p=1611

TinyBasicAS: Flex version of TinyBasic
http://www.thisiscool.com/tinybasicas.htm

Java runs in Flash-Waba VM Alchemy:
http://www.thisiscool.com/j2f.htm

The brainfuck programming language interpreter:
http://blog.onthewings.net/2009/10/08/brainflash-the-as3-brainfuck-interpreter/
http://wonderfl.net/c/njuL

Ascript:
http://code.google.com/p/ascript-as3/
https://github.com/softplat/ascript

hscript:
Parse and evalutate Haxe expressions. Haxe script is a complete subset of the Haxe language.
https://github.com/HaxeFoundation/hscript

Simplified JavaScript interpreter:
A JavaScript interpreter you can embed in your Flash ActionScript 3 projects. Can parse and execute most JavaScript and support async "await" statement that pauses the VM until a Promise is fulfilled.
https://github.com/sixsided/Simplified-JavaScript-Interpreter